Electric Field diagram question

1. Jan 30, 2017

Samuel1321

http://imgur.com/a/Hg23p 1. The problem statement, all variables and given/known data
In each of the figures below some electric field lines are drawn. But in most cases, there are mistakes. For each drawing, select which of the above rules are broken or if the diagram is essentially correct.

http://imgur.com/a/Hg23p

2. Relevant equations
Rule 1: direction from + to −
Rule 2: number proportional to charge
Rule 3: radial symmetry close to charge
Rule 4: spacing inversely proportional to field magnitude
Rule 5: field tangent to any line

3. The attempt at a solution

For the 1st question: Rule 1 is not violated, Rule 2 is violated since the charge is different, Rule 3 is not violated since there is symmetry, Rule 4 is not violated, Rule 5 is not violated

For the 2nd question: Rule 1 is not violated since it is going to the negative charge, Rule 2 I'm not sure, Rule 3 is violated since there is no symmetry, Rule 4 I don't know, Rule 5 is violated the electric field is not tangent to the field line

Thanks!

2. Jan 31, 2017

Cutter Ketch

Regarding the first one, it is hard to break rule two without also breaking rule 4.

Regarding the second one, why aren't you sure about rule 2? You were very sure about the first one. Why should this be different? I could make the same comment about rule 4.

All I can say about rule 5 is that it is hard not to violate when other rules are broken.